1. Field of The Invention
This invention relates to a new and improved minimum carryover container, and to a new and improved automated analysis system incorporating that container; both of which are particularly adapted for use in the automated successive analyses of a series of discrete sample liquids.
2. Description of the Prior Art
Although a wide variety of containers are, of course, known in the prior art, none are known which are configured or operable in the manner taught by this invention; or which can provide the particularly significant advantages of simplicity, low cost, absolute reliability, versatility of application, virtually limitless re-usability, and mimimization of carryover as are respectively provided by the container of this invention.
More specifically, although the reaction container or cuvette disclosed in U.S. Pat. No. 4,357,301 issued Nov. 2, 1982 to Michael M. Cassaday, et al, and ass to the assignee hereof, does function to provide a situs for the reaction of an aqueous sample liquid, and a reagent liquid, and does provide for the in situ colorimetric analysis of the duly reacted sample liquid; this container, being, either disposable or in no practical manner re-usable without the most thorough of washing (not disclosed), is clearly not directed as such to the minimization of sample liquid carryover. To the contrary, this container which is specifically disclosed as comprising a hydrophilic bottom surface having ridges or the like projecting upwardly therefrom, is designed to insure that an encapsulating film of an immiscible liquid as may surround a sample liquid segment dispensed into the container, is broken upon striking the bottom of the container to in turn insure sample and reagent liquid mixing and reaction within the container. As a result, contamination of the container by the sample liquid becomes a virtual certainty.
In like manner, although a number of automated, successive sample liquid analysis systems are known in the prior art which are made relevant to that of this invention by the disclosure of the use an immiscible isolation liquid to reduce sample liquid carryover through the generation of an isolation liquid based sample liquid stream, none are known which are configured or operable in the manner taught by this invention; or which can provide the particularly significant advantages of analysis system simplification, reduced costs in terms of both system fabrication and system operation, increased reliability, increased speed of operation, and increased sample liquid analysis accuracy as are respectively provided by the sample liquid analysis system of this invention.
More specifically, although the sample liquid analysis system disclosed in U.S. Pat. No. 3,479,141 issued Nov. 18, 1969 to W. J. Smythe, et al, and assigned to the assignee hereof, does operate satisfactorily to reduce sample liquid carryover through the generation of an immiscible isolation liquid based sample liquid stream; the means by which that stream is generated and the means by which the requisite sample liquid reagents and the like are added thereto in the requisite precise proportion(s), including the sample and recipient sides of a dialyzer, multi-tube peristaltic pumps, and conduit junctures and the like, are clearly more complex and costly, and less reliable than those of this invention, and are clearly less effective in reducing sample liquid carryover since the isolation liquid based sample liquid stream is only generated intermediate the sample analysis process. Too, the inherent limitations in peristaltic pump speed and dialysis rates limit the speed of operation of this analysis system in terms of sample liquid analyses per unit time to a number far below that which can be provided by the analysis system of this invention. In addition, the isolation liquid consumption rate of this system is much higher than that of the system of this invention, thus adding significantly to costs of system operation because appropriate isolation liquids are costly; while the inclusion of a dialyzer in this prior art analysis system significantly limits the versatility thereof in terms of the types of automated sample liquid analyses which can be performed thereby.
Similarly, although the sample liquid analysis system disclosed in U.S. Pat. No. 4,253,846 issued Mar. 3, 1981 to W. J. Smythe, et al, and assigned to the assignee hereof, also operates satisfactorily to reduce sample liquid carryover through the generation of an immiscible isolation liquid based sample liquid stream; the means by which that stream is generated and the means by which the requisite sample liquid reagents and the like are added thereto in the requisite precise proportion(s), including non-illustrated applicator means operatively associated with the sample liquid aspirating probe, and a complex assembly of poppet valve injectors and equally complex operatively associated actuating structures, are again clearly more complex and costly, and less reliable than those of this invention. In addition, the requirement for successive sample and reagent liquid introduction into the sample liquid stream inherently limits the speed of operation of this prior art analysis system in terms of the number of sample liquid analyses per unit time to a number far below that which can be provided by the analysis system of this invention.
Similarly, although the sample analysis system disclosed in currently pending application for U.S. patent of S. Saros, et al, Ser. No. 441,181 filed Nov. 11, 1982 and assigned to the assignee hereof, also operates satisfactorily to reduce sample liquid carryover through the generation of an isolation liquid based sample liquid stream, the means by which that stream is generated and the means by which the requisite sample liquid reagents and the like are added thereto in the requisite precise proportion(s), including an applicator shroud operatively associated with the sample and reagent liquids aspirating probe, and a complex sample-reagent liquids metering assembly requiring photodectors and stop valves and operatively associated operating structure, are again clearly more complex and costly, and far less reliable than those of this invention. In addition, the requirement for successive sample and reagent liquid aspiration and introduction into the sample liquid stream at the stream formation or "front end" of this prior art analysis system again inherently limits the speed of operation in terms of the number of sample liquid analyses which can be performed per unit time to a number far below that which can be provided by the analysis system of this invention.
Of course, the specified disadvantages with regard to high cost of each of the prior art analysis systems of U.S. Pat. Nos. 3,479,141 and 4,253,846, and the analysis system of currently pending application for U.S. patent Ser. No. 441,181 would, in each instance, virtually preclude the economically realistic paralleling thereof for use in multi channel analysis systems.
U.S. Pat. Nos. 4,357,301, 3,479,141 and 4,253,846, and currently pending application for U.S. patent Ser. No. 441,181, now indicated as containing allowable subject matter, are hereby incorporated by reference in this application.